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Previous issue date: 2012-08-04 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Perovskites oxides win importance by its properties and commercials applications,
they have a high thermal stability, have conductive properties, electrical, catalytic, electro
catalytic, optical and magnetic, and are thermally stable. Because of these properties, are
being widely studied as carriers of oxygen in the process of power generation with CO2
capture. In this work, the base carrier system La1-xMexNiO3 (Me = Ca and Sr) were
synthesized by the method via the combustion reaction assisted by microwave. were
synthesized from the combustion reaction method by microwave process. This method
control the synthesi`s conditions to obtain materials with specific characteristics.
The carriers calcined at 800 ? C/2h were analyzed by thermal analysis (TG-DTA), to
verify its thermal stability, X-ray diffraction (XRD) to verify the phase formation, with
subsequent refinement by the Rietveld method, to quantify the percentage of phases formed,
the surface area by BET method was determined, scanning electron microscopy (SEM) was
obtained to evaluate the material morphology and temperature programmed reduction (TPR)
was done to observe the metallic phase of the nickel. After all proposed characterization and
analysis of their results can be inferred to these oxides, key features so that they can be
applied as carriers for combustion reactions in chemical cycles. The final products showed
perovskite-type structures K2NiF4 (main) and ABO3. / ?xidos com estrutura tipo perovsquita destacam-se por suas diversas propriedades e
aplica??es comerciais, pois possuem alta estabilidade t?rmica, apresentam propriedades
condutoras, el?tricas, catal?ticas, eletrocatal?ticas, ?pticas e magn?ticas, al?m de serem
termicamente est?veis. Devido a estas propriedades, est?o sendo amplamente estudados como
carreadores de oxig?nio em processos de gera??o de energia com captura de CO2. Neste
trabalho, carreadores a base do sistema La1-xMexNiO3 ( Me = Ca e Sr) foram sintetizados a
partir do m?todo via rea??o de combust?o assistida por microondas. Este m?todo controla as
condi??es de s?ntese para obten??o de materiais com caracter?sticas espec?ficas. Os
carreadores calcinados a 800?C/2h foram analisados atrav?s de an?lise t?rmica (TG-DTA),
para verifica??o de sua estabilidade t?rmica; difra??o de raios-X (DRX), para verifica??o das
fases formadas, com posterior refinamento atrav?s do m?todo de Rietveld, para quantificar o
percentual das fases formadas; ?rea superficial pelo m?todo BET; microscopia eletr?nica de
varredura (MEV) e redu??o ? temperatura programada (TPR). Ap?s toda caracteriza??o
proposta e an?lise dos seus resultados pode-se inferir a esses ?xidos, caracter?sticas
fundamentais para que os mesmos possam ser aplicados como carreadores em rea??es de
combust?o por ciclos qu?micos. Os carreadores de oxig?nio obtidos possuem estruturas
perovsquitas do tipo K2NiF4 (principal) e ABO3.
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17659 |
| Date | 04 August 2012 |
| Creators | Melo, Vitor Rodrigo de Melo e |
| Contributors | CPF:06117988320, http://lattes.cnpq.br/3318871716111536, Pergher, Sibele Berenice Castella, CPF:50942611004, http://lattes.cnpq.br/5249001430287414, Barros, Joana Maria de Farias, CPF:85239658404, http://lattes.cnpq.br/1016070459137884, Melo, Dulce Maria de Ara?jo |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Qu?mica, UFRN, BR, F?sico-Qu?mica; Qu?mica |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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